<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="https://cdn.staticfile.org/react/16.4.0/umd/react.development.js"></script>
    <script src="https://cdn.staticfile.org/react-dom/16.4.0/umd/react-dom.development.js"></script>
    <!-- 生产环境中不建议使用 -->
    <script src="https://cdn.staticfile.org/babel-standalone/6.26.0/babel.min.js"></script>
</head>

<body>
    <div id="app">

    </div>
    <script type="text/babel">
        class App extends React.Component{
            constructor(props){
                super(props);
                this.state = {
                    msg:"state"
                }
            }
            render(){
                /* bind可以解决this关键字指向的问题 */
                return (
                    <h1 onClick={this.handleClick.bind(this)}>{this.state.msg}</h1> //this.setState可以改变state中的数据
                )
            }
            handleClick(){
                this.setState({
                    msg:"click"
                })
                console.log("event")
            }
        }
        ReactDOM.render(
           <App/>,
            document.getElementById("app")
        );
        
    </script>
</body>

</html>